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The Taodonggou group of Middle Permian is an important source rock in Taibei sag of Turpan-Hami basin. Due to its deep burial, drilling has only been revealed in recent years. Based on organic petrology and organic geochemistry experiments, this paper studies the organic petrology, organic geochemistry, sedimentary environment, and hydrocarbon generation potential of source rocks in Taibei sag, Turpan-Hami basin, and reveals the influence of the sedimentary environment on the organic matter abundance of source rocks. The results are as follows: (1) The organic matter of the Middle Permian source rocks in Taibei sag of Turpan-Hami basin is mainly sapropelite and exinite. The vitrinite is mainly vitrodetrinite, and the exinite is mainly lamalginiite. (2) The total organic carbon content value is 0.55–6.08 wt %, and the average value is 2.58 wt %. The PG value ranges from 0.78 mg HC/g to 30.86 mg HC/g, and the average value is 4.88 mg HC/g. Chloroform asphalt “A” is 0.046–0.8767 wt %, and the average value is 0.285 wt %. The types of organic matter are mainly III and II–III, and the Ro value is 0.628–1.49 wt % (average = 0.988 wt %). The Tmax distribution is 329–465 °C. The average temperature is 434.7 °C, which is in the mature stage (oil window stage). The Middle Permian source rocks are mainly very good to excellent source rocks with a good hydrocarbon generation potential. (3) The source rocks are deposited in a semihumid and semiarid climate. Organic matter is input as a mixed source. The early and late stages is dominated by terrestrial higher plants. The middle stage is dominated by lower aquatic organisms, and the sedimentary environment consists of weak reduction and weak oxidation environments. (4) In the study area, the abundance of organic matter has a weak negative correlation with CPI and a positive correlation with Pr/Ph and ∑C21–/∑C22+. Under the coaction of paleoclimate, organic matter input, and redox environment, the enrichment model of organic matter with high productivity and weak oxidation environment characteristics can also form excellent source rocks. This study is of great significance and provides theoretical guidance for the exploration of deep oil and gas resources.

Fracture and cleats development controls the permeability of coal reservoirs, while the migration of coal fines can block fractures and affect coalbed methane (CBM) production performance. To revea...

Focusing on vertical multi-layer superimposition of unconventional natural gas reservoirs in coal-bearing strata, research on the co-production of tight gas and coalbed methane from a single wellbore was conducted. This study intended to obtain maximum economic benefit of a single well from multi-layers. According to the vertical combination of tight sandstone and coal in the eastern Ordos Basin, the reservoir combinations were classified into direct contact, fracture connected, and non-contact types. Based on the economic benefit of co-production, the inter-layer interference coefficient and applicability coefficient were established. The productivity of tight gas and coalbed methane co-production from one wellbore was numerically simulated using the black oil model. The results indicated that with increase in reservoir permeability, thickness, and average pressure, as well as the decrease in reservoir differential pressure, the combined gas production increased. Gas production rate from different reservoir combination types can be ranked in the following order: direct contact type > fracture connected type > non-contact type. In addition, with increase in permeability ratio (sandstone permeability vs. coal permeability) and average pressure, as well as with decrease in differential thickness and differential pressure, the co-production applicability increased. In addition, for different reservoir combinations, non-contact type co-production can be the first choice, and the next choice is fracture connected type. The results can be beneficial for conducting co-production choice in different unconventional natural gases superimposed basins.

The high gas content of deep coal seams is a driving force for the exploration and development of deep coalbed methane (CBM). The nanoscale pores, which are the main spaces for adsorption and storage of CBM, are closely related to the burial depth. Based on integrated approaches of vitrinite reflectance (Ro), maceral composition, scanning electron microscope (SEM), proximate analysis, fluid inclusion test, low-temperature N2 adsorption–desorption, and CH4 isothermal adsorption, the nanoscale pore structure of coals recovered at depths from 650 to 2078 m was determined, and its influence on the CH4 adsorption capacity was discussed. The results show that the coal rank has a good linear relationship with the current burial depth of the coal seams; that is, the influences of the burial depth on the coals can be reflected by the influences of the coal rank on the coals. With the increase in the coal rank, the moisture and volatile content decrease, and the fixed carbon content increases. The variation in the pore volume and specific surface area with the increase in the coal rank can be divided into two stages: the rapid decline stage (when 0.75% 1.0%, the FD of the micropores is close to 2. This indicates that with the increase in the degree of coalification, the surface of the micropores is simpler. The above results show that the gas adsorption capacity of coal first slightly decreases (when 0.75% < Ro < 1.0%) and then increases (when 1.0% < Ro < 1.35%), and the coincident results are shown in the Langmuir volume (VL) test results.

Tarim Basin is the largest Petroliferous basin in China, while its shale gas development potential has not been fully revealed. The organic-rich black shale in middle Ordovician Heituao Formation from Tadong low uplift of Tarim Basin has been considered as an important source rock and has the characteristic of large thickness, high organic matter content and high thermal maturity degree. To obtain its development potential, geochemical, mineralogical and mechanics research is conducted based on Rock-Eval pyrolysis, total organic carbon (TOC), X-ray diffraction (XRD) and uniaxial compression experiments. The results show that: (1) the TOC content ranges between 0.63 and 2.51 wt% with an average value of 1.22 wt%, the Tmax values are 382–523 °C (average = 468.9 °C), and the S2 value is relatively low which ranges from 0.08 to 1.37 mg HC/g rock (averaging of 0.42 mg HC/g rock), (2) the organic matter of Heituao shale in Tadong low uplift show poor abundance as indicated by low S2 value, gas-prone property, and post mature stage (stage of dry gas). (3) Quartz is the main mineral component in Heituao shale samples, accounting for 26–94 wt% with an average of 72 wt%. Additionally, its Young’s modulus ranges from 20.0 to 23.1 GPa with an average of 21.2 GPa, Poisson’s ratio ranges between 0.11 and 0.21 (average = 0.15), (4) the fracability parameter of brittleness index (BI) ranges between 0.28 and 0.99 (averaging of 0.85), indicating good fracability potential of Heituao shale of Tadong low uplift and has the potential for shale gas development. This study reveals the shale gas accumulation potential in middle Ordovician of the Tarim Basin, and beneficial for future exploration and production practice.

Accuracy is a key factor in high-resolution remote sensing and photogrammetry. The factors that affect accuracy are imaging system errors and data processing errors. Due to the complexity of aerial camera errors, this paper focuses on the design of digital aerial camera systems and the means to reduce system error and data processing inefficiencies. There are many kinds of digital aerial camera systems at present; however, these systems lack a unified physical model, which ultimately leads to more complicated designs and multi-camera modes. Such a system is complex and costly, as it is easily affected by factors such as vibration and temperature. Thus, the installed accuracy can only reach the millimeter level. Here, we describe a unified physical structure for a digital aerial camera that imitates an out-of-field multi-charge-coupled device (CCD), an in-field multi-CCD, and once-imaging and twice-imaging digital camera systems. This model is referred to as the variable baseline-height ratio spatiotemporal model. The variable ratio allows the opto-mechanical spatial parameters to be linked with height accuracy, thus providing a connection to the surface elevation. The twice-imaging digital camera prototype system and the wideband limb imaging spectrometer provide a transformation prototype from the current multi-rigid once-imaging aerial camera to a single rigid structure. Thus, our research lays a theoretical foundation and prototype references for the construction and industrialization of digital aerial systems.

The heterogeneity and micropores distribution of coal and shale reservoirs make them difficult to be quantitatively characterized by quick and economical approaches. A new method based on the atomic force microscopy (AFM) test is applied to reveal the pore structure and surface roughness of coal and shale with the help of open source Gwyddion software. The surface morphologies of coal and shale are reconstructed in two and three dimensions by AFM data, and the surface roughness is evaluated by parameters like mean roughness, mean square roughness, surface skewness, and kurtosis coefficient. Pores of different scales are quantitatively recognized by the Threshold and Watershed methods, and the two methods are combined for more accurate results. The Threshold method is appropriate for characterizing pores of 10–500 nm and the Watershed method is more suitable for 1–200 nm pores. Parameters such as pore numbers, plane porosity, pore size distribution, pore surface area and pore volume are obtained based on the combined method in revealing pores of 1–500 nm range. The tested samples are also evaluated by scanning electron microscope images, which shows a reliable consistency between the pore scales compared with the AFM results. The method, using easily accessed AFM experiment and open source software, can be widely used in characterizing the surface roughness and pore structure of unconventional oil and gas reservoirs.

With the novel capabilities of engineering the optical wavefront at the nanoscale, the dielectric metalens has been utilized for fluorescence microscopy imaging system. However, the main technical difficulty is how to realize the achromatic focusing and light modulation simultaneously by a single-layer metalens in the two-photon excitation STED (TPE-STED) endomicroscopy imaging system. Herein, by combining the spatial multiplexing technology and vortex phase modulation, a single-layer multitasking vortex-metalens as a miniature microscopy objective on the end of fiber was proposed. The multitasking vortex-metalens with 36-sectors interleaving (diameter of 100 μm) could focus the excitation beam (1050 nm) and depletion beam (599 nm) to the same focal distance, modulate a doughnut-shaped depletion spot with vortex phase and reshape the focal spots to further make improvement in the quality and symmetry. According to the TPE-STED theory, a symmetrical effective fluorescent spot with the lateral resolution of 30 nm was obtained by the proposed metalens. Thus, with the advantage of ultra-compact and lightweight, we prospect that the subminiature multitasking metalens will help guide future developments in high-performance metalenses toward high-resolution and real-time images for deep biological tissue in vivo and enable scientific high-end miniature endomicroscopy imaging system.

4Pi stimulated emission depletion (STED) microscopy shows outstanding three-dimensional (3D) isotropic super-resolution imaging performance. However, this technology is still difficult for achieving long-term studying of the synapses that are deeply embedded inside brain tissue. Metalens, which can realize arbitrary nanoscale amplitude, phase, and polarization modulations, is a very useful tool to solve this limitation. In this paper, an ultracompact two-photon 4Pi STED microscopy involved two multifunctional metalenses patterned on the two fiber facets respectively for focusing the excitation and depletion laser beams to the same position was proposed to realize the 3D isotropic super-resolution imaging. The designed complementary structure of two metalenses and the optimized pupil ratio β assured the symmetry of the STED spot. Furthermore, the isotropic super-resolution of 27 nm was theoretically implemented based on the two-photon STED theoretical model. Our approach will greatly increase the viability of the 3D super-resolution morphological imaging in the deep brain.

Coal structure directly correlates to permeability and hydraulic fracturing effects. Underground coal mining indicates that a single coal section generally contains multiple coal structures in superposition, making how to recognise the coal structure combination and predict its influence on coal permeability a challenging problem. Based on well-drilling sampled cores, the geological strength index (GSI), and well-logging data, the DEN, GR, CALX, and CALY were selected to establish a model to predict GSI by multiple regression to identify coal structure from 100 coalbed methane wells. Based on fitting GSI and corresponding permeability test values, injection fall-off (IFO) testing, and hydraulic fracturing results, permeability prediction models for pre- and post-fracturing behaviour were established, respectively. The fracturing effect was evaluated by the difference in permeability. The results show that a reservoir can be classified into one of nine types by different coal structure thickness proportion (and combinations thereof) and the fracturing curves can be classified into four categories (and eight sub-categories) by the pressure curve. Up-down type I and type II reservoirs (proportion of hard coal &gt, 60%) and intervening interval type I reservoir (proportion of hard coal &gt, 70%) are prone to form stable and descending fracturing curves and the fracturing effects are optimal. Intervening interval type II (hard coal:soft coal:hard coal or soft coal:hard coal:soft coal &asymp, 1:1:1) and up-down type III (hard coal:soft coal =1:1) form descending type II, rising type I and fluctuating type I fracturing curves and fracturing effect ranks second, up-down type IV and V (proportion of hard coal &lt, 40%), interval type III (proportion of hard coal &lt, 30%), and multi-layer superposition-type reservoirs readily form fluctuating and rising fracturing curves and fracturing effects therein are poor. The research results provide guidance for the targeted stimulation measured under different coal structure combinations.

Tight gas is an important unconventional resource with continuous consumption demand, and co-production from multi-layers are becoming an inevitable choice for areas with low reserve abundance. The Ordos basin contain tight gas production from generally the whole Permian, recording sandstones deposited from transitional to terrestrial environments. In order to reveal the reservoir sensitivities of different layers, petrophysical and sensitivity experiments were conducted with samples from members of different sedimentary environment, i.e., Tai 2 Member (P1t2, coastal environment), Shan 1 Member (P1s1, deltaic environment), He 8 Member (P2x8, deltaic-fluvial environment), He 4 Member (P2s4, fluvial environment), and Qian 5 Member (P3s5, braided fluvial environment) of Permian. The results showed: (1) The sandstones of P1t2, P1s1, P2x8, P2s4, and P3s5 are dominated by feldspathic litharenite, litharenite, lithic arkose, litharenite, and lithic arkose, respectively; (2) From P1t2 to P3s5, the content of illite decreases, those of chlorite and illite/smectite (I/S) increase, and kaolinite firstly increases and then decreases (the trend changed in P2s4); (3) The permeability of all the analyzed sandstones ranges between 0.2 and 0.6 mD, the average porosity between 5.7% and 8.2%, with mercury withdrawal efficiency between 32.8% and 42.1% and average median radius between 0.10 and 0.20 μm; (4) All the sandstones have medium–weak flow rate sensitivities, with medium–weak (P1t2), medium (P1s1), medium (P2x8), medium (P2s4), and medium–weak (P3s5) water sensitivities and weak (P1t2), medium–weak (P1s1), medium–weak (P2x8), medium–weak (P2s4), and medium (P3s5) alkali sensitivities. The flow rate sensitivities are mainly influenced by pore structure and the quartz content, while water sensitivities are affected by pore structure, I/S and illite contents, and the alkali sensitivities are correlated with pore structure and kaolinite, I/S, and feldspar contents. The results can be beneficial for tight gas production engineering choices and strategies for improving gas production.

The physical properties of coal reservoirs, i.e., porosity, permeability, fractures, and coal structures, are generally evaluated based on its structural morphology, however, its tectonic evolution history plays a much more important role. The key problems associated include the time when the dominant variations on properties of coal occurs and how to quantitatively characterize the influences of different tectonic movements. Based on field joint observations and well logging (micro-resistivity imaging logging (MIL), interval transit time (DT24), density (DEN), and natural gamma-ray (GR)) interpretations, the paleotectonic stress fields and tectonic traces were recovered and the present coal structures were identified. Subsequently, the quantitative correlation between the tectonic deformation and coal reservoir property were established with fluid intrusion tested porosity and permeability and scanning electron microscope (SEM) results. The results showed that the maximum horizontal compressive stress was oriented at the NW-SE direction in Yanshanian and at the NEE-SWW direction in the Himalayan period as obtained from hundreds of joint measurement and fracture interpretation results. Six combinations (by superposition of anticline, syncline, and the flanks) from the Yanshanian and Himalayan movements were found, which indicate different deformation degrees. The maximum tectonic curvature (r'), which occurred in either the Yanshanian or Himalayan period, shows differences at different structural areas and reflects the real deformation degree of coal seam in geological history. When r' 35 × 10−6 m−1, granulated coals are dominant. Mylonitized coals are barely developed in the study area. With the increase of deformation degrees of coal seams, the number of microfractures increases and fracture stretches tend to be more complicated. When r' 25 × 10−6 m−1, the coal cores are much too broken for drilling core samples), with the increase of r', the displacement pressure (Pd) achieved by mercury intrusion method decreases in an linear form, and the permeability tested by helium presents a linear growth. However, the porosity shows a weak correlation with r', mainly caused by the great burial depth and long-term compaction resulting in low porosity ranges (2.8%–8.1%) with little difference shown. This presents an applicable method for evaluating the influence of tectonic movement on the physical properties of coal during different times and would benefit the evaluation of coalbed methane reservoirs in the study area as well as other coal basins in the world.

This study assessed recently launched multispectral sensors to map seagrass properties for a ~ 150 km2 shallow bank in Moreton Bay, Australia. We utilised a previously developed semi-automated, obj...

The α-enolase (ENO1) plays pivotal roles in several types of cancer, but its clinical significance, functional role, and possible mechanism in colorectal cancer (CRC) have remained unclear. Expression level of ENO1 in CRC tissues was examined by qRT-PCR, Western blot, and immunohistochemistry. The effects of ENO1 on cell growth were investigated by MTT, colony formation, flow cytometry assays, and in vivo tumorigenic capacity analysis. The impacts of ENO1 on cell migration and invasion were also explored by scratch-healing, Transwell or Matrigel chamber assays, and in vivo metastatic capacity analysis. Our results showed that the expression level of ENO1 was significantly elevated in CRC tissues. High expression level of ENO1 was associated with disease progression in CRC patients. Overexpression of ENO1 in HCT116 cell line promoted cell proliferation, migration, and invasion in vitro as well as tumorigenesis and metastasis in vivo. In other hand, ablation of ENO1 in HCT116 cells led to totally reverse effects. Mechanistically, we revealed ENO1 could regulate AMPK/mTOR signaling pathway. AMPK pathway activation or mTOR pathway suppression blocked these ENO1 induced alterations. Together, our results demonstrated that ENO1 is a potent promoter of CRC genesis and metastasis at least in part though regulating AMPK/mTOR pathway. These findings also suggested that ENO1 may be a promising therapeutic target in CRC patients.

Land cover classification and change detection plays an important role and significance in geographical conditions and environmental monitoring, which is a hot and difficult remote sensing topic. The difficulties in land cover remote sensing are how to realize the detecting by a quantitative and automatic way. At present, there is no general classification algorithm which is proper for different multi-remote sensing data's quantitative processing. In this paper, a multi-source remote sensing image classification method based on spectral reflectance characteristics is studied. Using the geometric and radiometric calibration parameters, sensor spectral response function and satellite-earth-sun's orbit parameters, multi remote sensing data's ground reflectance and land cover monitoring classification could be realized automatically. In earthquake evaluation, two GF2 multispectral remote sensing images are processed. The typical land cover elements, including vegetation, water and bare land, are detected and classified. The evaluation of land cover change proportion is calculated quantitatively and automatically.

// Chunyan Liu 1 , Lina Wang 1 , Weiwen Chen 1 , Shihu Zhao 1 , Chunli Yin 1 , Yani Lin 1 , Anli Jiang 1 , Pengju Zhang 1 1 Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, 250012, P.R. China Correspondence to: Pengju zhang, e-mail: zhpj@sdu.edu.cn Keywords: ABIN-2, deubiquitylase, miR let-7a, NF-κB, USP35 Received: March 09, 2015 Accepted: June 16, 2015 Published: June 26, 2015 ABSTRACT Ubiquitin specific protease 35 (USP35) is a member of deubiquitylases (DUBs). It remains largely unknown about the biological role and the regulation mechanism of USP35. Here, we first identified miR let-7a as a positive regulator of USP35 expression and showed that USP35 expression positively correlates with miR let-7a expression in different cancer cell lines and tissues. Then, we showed that USP35 expression was decreased dramatically in the tumor tissues compared with the adjacent non-cancerous tissues. USP35 overexpression inhibited cell proliferation in vitro and inhibited xenograft tumor growth in vivo . Furthermore, we revealed that USP35 acts as a functional DUB and stabilizes TNFAIP3 interacting protein 2 (ABIN-2) by promoting its deubiquitination. Functionally, both ABIN-2 and USP35 could inhibit TNFα-induced NF-κB activation and overexpression of ABIN-2 alleviated USP35-loss induced activation of NF-κB. Collectively, our data indicated that miR let-7a-regulated USP35 can inhibit NF-κB activation by deubiquitination and stabilization of ABIN-2 protein and eventually inhibit cell proliferation. Overall, our study provides a novel rationale of targeting miR let-7a-USP35-ABIN-2 pathway for the therapy of cancer patients.

FBXW7 (F-box and WD40 domain protein 7) is a tumor suppressor frequently inactivated in human cancers. The precise molecular mechanisms by which FBXW7 exerts antitumor activity remain under intensive investigation and are thought to relate in part to FBXW7-mediated destruction of key cancer-relevant proteins. Enolase 1 (ENO1) possesses oncogenic activity and is often overexpressed in various human cancers, besides its critical role in glycolysis. However, the detailed regulatory mechanisms of ENO1 expression remain unclear. Here we show that the elevated expression of ENO1 was identified in FBXW7-depletion HCT116 cells through two-dimensional protein electrophoresis and mass spectrometry assays (2DE-MS). Subsequent western blotting and immunohistochemical assays confirmed that ENO1 expression reversely correlates with FBXW7 expression in several cells and colon cancer tissues. Furthermore, we show that FBXW7 physically binds to ENO1 and targets ENO1 for ubiquitin-mediated degradation. Functionally, we found that FBXW7 suppresses the ENO1-induced gene expression, lactate production, cell proliferation and migration. These findings suggest that ENO1 is a novel substrate of FBXW7, and its activity can be negatively regulated by FBXW7 at the posttranslational level. Our work provides a novel molecular insight into FBXW7-directed tumor suppression through regulation of ENO1.

Objective To investigate the role of miR-221/222 in cell proliferation and apoptosis in human prostate cancer cells, and examine the effects of miR-221/222 on caspase-10 expression. Methods Prostate cancer cells were transfected with miR-221/222 mimics or inhibitors. Cell proliferation was assessed by MTT assay. The expression levels of miR-221/222 were detected with quantitative real-time PCR. Apoptosis was induced with TNF-α/CHX treatment, and evaluated by Hoechst 33342 staining, propidium iodide (PI) flow cytometric analysis, caspase-3 activity measurement, and Western blot analysis. Luciferase activity assay, quantitative real-time PCR, and Western blot were performed to evaluate the effects of miR-221/222 on caspase-10 expression. Results Our results showed that miR-221/222 could promote the proliferation of prostate cancer cells, including LNCaP and PC3 cells. After transfection and apoptosis induction, Hoechst 33342 staining and PI flow cytometric assay showed that apoptosis was dramatically decreased in prostate cancer cells treated with miR-221/222 mimics. Moreover, caspase-3 activity was dramatically decreased, and the cleaved forms of caspase-3 were reduced, in the miR-221/222 mimic-treated group. On the contrary, miR-221/222 knockdown sensitized the prostate cancer cells to TNF-α/CHX-induced apoptosis. In addition, a negative correlation was observed between the expressions of miR-221/222 and caspase-10 in prostate cancer cells. miR-221/222 could repress the expression of caspase-10, which was confirmed by the luciferase reporter assay. Conclusion miR-221/222 promote cell proliferation and repress apoptosis, through suppressing caspase-10, in prostate cancer cells. Our results provide promising evidence for the miRNA-based therapeutic strategy of prostate cancers.

High-precision and real-time remote sensing imaging system is an important part of remote sensing development. Holography is a method of wave front record and recovery which was presented by Dennis Gabor. As a new kind of holography techniques, Optical scanning holography (OSH) and remote sensing imaging are intended to be combined together and applied in acquisition and interference measurement of remote sensing. The key principles and applicability of OSH are studied and the mathematic relation between Fresnel Zone Plate number, numerical aperture and object distance was deduced, which are proved to be feasible for OSH to apply in large scale remote sensing. At last, a new three-dimensional reflected OSH remote sensing imaging system is designed with the combination of scanning technique to record hologram patterns of large scale remote sensing scenes. This scheme is helpful for expanding OSH technique to remote sensing in future.

Abundant real-time image data are generated during aerial survey period. Through design of a digital storage system, data from a newly twice-imaging airborne camera device are timely and faultlessly stored in an IDE (Integrated Drive Electronics) hard disk. The system has data acquisition, storage and preview functions. Particularly, it receives data burst of nearly 58 MB/s and stores them within 2 seconds. And then, personal computer reads them out from hard disk through USB interface for subsequent processing, analyzing and serving.

According to the specified standard of airborne Photogrammetry, digital airborne cameras must have higher performance than ordinary civil cameras, which must shoot with shorter time interval and will generate huge data stream. In this paper, a digital airborne camera is designed and implemented in a single FPGA chip as a SOPC approach. The functions of image acquisition, storage and display are implemented by the hardware logic while the functions of control and communication are implemented by the software running in the soft processor core. With the hardware and software cooperation in the single FPGA, the image whose format is RAW is previewed to a VGA monitor while the raw image data can be transferred to an ATA5 hard disk in Ultra DMA mode 4. In testing, this data storing system can achieve the burst speed to 57MB/s and average speed to 25.43MB/S.

In this paper, a ground-based teaching and experimental simulation system for earth observing digital aerial remote sensing is introduced. The authors give its construction, key technologies and implementation. This system can simulate the whole process of acquiring remote sensing images, which makes it more vivid for students to understand all the sectors of aerial remote sensing. The system fills the gap in teaching and experimental instruments for earth observing digital aerial remote sensing and makes the course of photogrammetry and remote sensing more complete. The achievement is awarded the '2006 Cooperation Prize for China University and Enterprise.

It is the coexisting time between film and digital imaging. Both film aerial camera and digital one have their particular imaging principles, characteristics and complementarities between them. In this paper, a new convertible aerial camera is developed to integrate film and CCD sensors, named as twice-imaging scheme. Some experiments have been carried out for the feasibility of the scheme. This convertible aerial camera system has both film and digital advantages. It can be used in different aspects of aerial remote sensing, surveying and mapping.